Information storage devices can be used to retrieve and/or store data in computers and other consumer electronics devices. A magnetic hard disk drive is an example of an information storage device that includes one or more heads that can both read and write data onto a magnetic storage disk. In a magnetic hard disk drive, each read/write head can be a sub-component of a head gimbal assembly (HGA). The read/write head typically includes a slider and a read/write transducer. The read/write transducer typically comprises a magneto-resistive read element (e.g., so-called giant magneto-resistive read element, or a tunneling magneto-resistive read element), and an inductive write structure comprising a flat coil deposited by photolithography, and a yoke structure having pole tips that face a media disk. The HGA typically also includes a suspension assembly that includes a mounting plate, a load beam, and a laminated flexure to carry the electrical signals to and from the read head. The read/write head is typically bonded to a tongue feature of the laminated flexure.
The HGA, in turn, can be a sub-component of a head stack assembly (HSA) that typically includes a plurality of HGAs, a head actuator, and a flex circuit. The mounting plate of each suspension assembly can be attached to an arm of the head actuator (e.g., by swaging), and each of the laminated flexures can include a flexure tail that is electrically connected to the HSA's flex circuit (e.g., by solder reflow bonding or ultrasonic bonding). The angular position of the HSA, and therefore the position of the read heads relative to data tracks on the disks, can be actively controlled by the head actuator which is typically driven by a voice coil motor (VCM). Specifically, electrical current passed through a coil of the VCM can apply a torque to the head actuator, so that the read head can seek and follow desired data tracks on the spinning disk.
Magnetic hard disk drives can be sensitive to low levels of specific gaseous contaminants. These contaminants can be caused by an outgassing of adhesive or other materials used within disk drives or unintended contaminants from materials and processes used in building magnetic recording drives or by contamination in environment external to the disk drive that can adsorb and react on head and disk surfaces (e.g., at the head-disk interface). When the local temperatures due to head-disk contact or heat-assisted magnetic recording (HAMR) writing and reading raise the local temperatures, these chemical reactions can occur at higher rates and additional reactions can occur. When the products of these reactions are solid or liquid materials, they can accumulate, in particular on heads, and lead to excessive head-disk contacts that raise the interfacial temperatures even higher, further speeding up this process and eventually resulting in head-disk failures. In addition, these solid or liquid materials on heads can cause an increase in head-disk spacing and degradation of magnetic performance. Very low concentrations of contaminants within the disk drive are enough to lead to these failures, and therefore it is difficult to fabricate and operate disk drives that would not have some of these contaminants present.